Field of the Invention
[0001] The present invention relates to solid compositions which release a vapour containing
at least one essential oil when exposed to effective air flow. The present invention
also relates to methods of producing the solid compositions; and to methods of disinfecting
air conditioning systems using the solid compositions.
Background of the Invention
[0002] Tea tree oil is a natural essential oil from a tree of the class Myrtenceae, especially
of Melaleuca. Tea tree oil has been used as a broad spectrum topical antiseptic for
more than 70 years. In recent times, the anecdotal evidence as to the antimicrobial
efficacy of tea tree oils has been substantiated by scientific evidence. Such evidence
can be found in the work of Carson, C.F. and Riley, T.V,
Antimicrobial activity of the Major Components of the essential oil of Melaleuca Alternifolia, Journal Applied Bacteriology, 78, 264-269 (1995); C.F. Carson, B.D. Cookson, H.D.
Farrelly and T. V Riley,
Susceptibility of methicillin-resistant Staphylococcus aureaus to the essential oil
of Melaleuca Alternifolia, Journal Antimicrobial Chemotherapy, 35, 421-424 (1995); and Carson, C.F., Hammer,
K,A. and Reiley, T.V. (1996)
In vitro activity of the essential oil of Melaleuca Alternifolia against Streptococcus
spp. Journal of Antimicrobial Chemotherapy 37: 1177-1178.
[0003] It is well recognised that commercial, industrial and hospital air conditioning ducting
can be a major source of infection and re-infection in public and private buildings.
The World Health Organisation (WHO) reported its findings on this subject in 1988.
This report in brief stated that biological air contaminants in indoor air have been
associated with half of all absenteeism and reduced worker efficiency discovered in
the report.
[0004] International publication No. WO 88/10122 (Commonwealth Industrial Gases Ltd) describes
the use of a biocidal composition comprising an oil of Melaleuca in disinfecting air
conditioning systems. This procedure involves solubilising the tea tree oil in both
ethanol and carbon dioxide and delivering the solubilised tea tree oil by gaseous
carbon dioxide into air conditioning ducting. The procedure therefore requires a constant
supply of carbon dioxide by way of carbon dioxide gas cylinders. Specialised equipment
such as a high pressure rated gun, hoses and other automatic delivery apparatus are
also required. In addition to the fact that this procedure requires specialised equipment
and highly trained personal, the possible hazards associated with the use of carbon
dioxide in these procedures are well documented. A safer and more cost effective procedure
for disinfecting air conditioning systems is therefore desirable.
[0005] The positive effects of dispersing pleasant aromatic essential oil odours into public
building air space are now well described in the medical literature. The traditional
manner for achieving this is by the use of either electric diffusers or by candle
warmed water or oil dispersed essential oil burners.
[0006] At the Plane Tree Public Hospital in California patients are given a choice of fragrances.
In the St Croix Valley Memorial Hospital, Wisconsin, natural fragrances are used to.counteract
unpleasant odours and to generally improve the atmosphere of all patient care and
amenity rooms. The Sloane Kettering Institute in New York has reported that the use
of Heliotropin, a vanilla like perfume, has significantly-reduced stress in cancer
patients. Lavender and Camomile essential oils are now in regular use in hospitals
in the United Kingdom. Where elderly patients have demonstrated a tendency to insomnia
the use of lavender has been found to lead to less restlessness and an actual increase
in the number of hours sleep.
[0007] At the Japan School of Medicine the worker Sagano has reported that the use of natural
fragrance will help both in the relaxation of staff and patients. International Airlines
as Virgin Airlines and New Zealand Airlines are using pure essential oils to assist
customers overcome travel fatigue and jet lag. International Hotel Groups as the Marriott
Chain use essential oil odours in the lobby areas of many of their hotels.
[0008] In all of the examples cited above traditional methods of dispersing the natural
essential oil odours are employed. It is desirable to develop a method of dispersing
essential oils which eliminates the need for electrical or candle or other such diffusers.
[0009] WO 92/12695 and US 5,009,890 refer to burn treatment products which are gels including
tea thee oil.
Summary of the Invention
[0010] The present inventors have now developed a solid composition which releases microscopic
essential oil vapour when exposed to an effective flow of gas such as that generated
by an air conditioning system. When placed in air conditioning ducts, solid compositions
of the present invention release an essential oil vapour. In cases where the essential
oil used in the solid composition exhibits antimicrobial activity, such as tea tree
oil, the solid compositions release a germicidal oil vapour. These compositions therefore
provide a relatively safe and inexpensive means for dispersing essential oils in a
given environment or for disinfecting air conditioning systems.
[0011] Accordingly, in a first aspect the present invention provides use of a solid composition
for disinfecting an air conditioning system, the composition including a gum material
and tea tree oil wherein the solid composition releases vapour containing the tea
tree oil when exposed to an effective flow of gas.
[0012] The gum material may be any material classified as a gum or hydrocolloid including
proteins, polysaccharides (for example, microbial polysaccharide exudates), carbohydrates
and celluloses or mixtures thereof.
[0013] In a preferred embodiment, the gum material includes carrageenans extracted from
red seaweeds.
Rhodophyeae-Gigartinales, families
Gigartinaceae and
Solieriaceae and example species
Eucheuma cottinii, Chondrus crispus, Eucheuma spinosan and
Gigarta stellata are suitable red seaweeds for a source of primary gum materials.
[0014] In a further preferred embodiment the carrageenans include kappa, iota or lambda
fractions or mixtures thereof.
[0015] In another preferred embodiment the gum material includes a galactomannan. Preferably,
the galactomannan has a molecular weight of approximately 300,000 and is non-ionic.
The galactomannan may be locust bean gum derived from the legume
Ceratonia siliqua.
[0016] In another preferred embodiment the gum material includes a microbial exudate. The
exudate may be derived from a bacterium such as
Xanthomonas campestris. The microbial exudate may be Xanthan gum.
[0017] In a more preferred embodiment the gum material includes a mixture of two or more
materials selected from carrageenans, locust bean gum and Xanthan gum.
[0018] Preferably, the gum material is present in the solid composition at a concentration
of between 2 and 10 wt% more preferably between 3 and 6 wt%.
[0019] The invention further provides a solid composition including tea tree oil and from
2 to 10 wt% of a gum material wherein the solid composition releases vapour containing
the tea tree oil when exposed to an effective flow of gas.
[0020] In a further preferred embodiment deionised water is used to prepare the gum material
solution. Preferably the pH of a 1% solution of the gum material solution is in the
range of 7 to 9.
[0021] The term "essential oil" when used herein encompasses both synthetic essential oils
and naturally occurring essential oils. Non-limiting examples of essential oils are
oils of various fruits such as apple, cherry, pineapple and the like, oils of various
woods such as cedar, pine, briar and the like, oils of various flowers or herbs such
as roses, violets, tobacco flowers and the like, and other such fragrances such as
peppermint, menthol, camphor, methyl salicylate, eucalyptus, parachlor benzene, acetates
and in general essential oils such as alcohols, aldehydes, esters, terpenes, tars,
phenols, thymols and the like.
[0022] In one preferred embodiment the essential oil exhibits antimicrobial activity. Non-limiting
examples of oils which exhibit antimicrobial activity include oils obtained from tea
trees, thyme, lemongrass, lemons, oranges, anise, clove, roses, lavendar, citronella,
eucalyptus, pepermint, camphor, sandalwood and cedar and combinations thereof.
[0023] In a preferred embodiment the essential oil is an aromatic oil or a tea tree oil
or a mixture thereof.
[0024] The aromatic oil may be selected from one or more of the group consisting of heliotropin,
lavender, camomile, a lemon scented oil (such as the oil of
Leptospermum liversidgeii), sandalwood and jasmine.
[0025] The essential oil of the species
Leptospermum liversidgeii has a unique and long lasting natural lemon odour. The present inventors have found
that compared to other lemon scented species (notably
Leptospermum petersoni) this species delivers the most pleasant of lemon odours and does so for the longest
duration.
[0026] In a further preferred embodiment, the solid composition also includes a fixative.
By "fixative" we mean a component which prolongs the evaporation rate of an aromatic
oil.
[0027] The fixative may be selected from the group consisting of musk ketone, coumarin,
eugenol and vanillin. The natural hydrocarbon component eugenol is a preferred fixative
for fragrant materials.
[0028] In the oil of
Leptospermum liversidgei, eugenol is present in relatively high amounts. This factor combined with the other
constituents such as citronellal, alpha pinene, linalool and thymol work together
to produce naturally a long lasting pleasant lemon aroma. The present inventors have
found that by combining the natural fixative elements present in the oil of
Leptospermum liversidei, unique and pleasant long lasting aromatic blends containing lavender or camomile
can be produced. The finished aroma can have a lemon scent or it can display the fragrance
of lavender or camomile. These examples are non-limiting and any combination of fragrances
that can be incorporated into solid gum compositions are encompassed by the present
invention.
[0029] Preferably, the essential oil is present in the solid composition at a concentration
of between 5 and 20% v/v, more preferably between 10 and 15% v/v.
[0030] The essential oil may be solubilised by any known means such as by admixture with
an alcohol or a surfactant or a mixture thereof. The alcohol may be ethanol, propan-2-ol
(isopropyl alcohol), propylene glycol or methanol.
[0031] In a preferred embodiment, the essential oil is solubilised by admixture with a non-ionic
surfactant which allows a low weight surfactant to weight of tea tree oil composition.
Preferably, the surfactant is an alcohol ethoxylate. In a more preferred embodiment,
the alcohol ethoxylate is polyoxyethylene (2) oleyl ether.
[0032] In a second aspect the present invention provides a method of solubilising an essential
oil which includes
i) heating a predetermined amount of an alcohol ethoxylate to a temperature of between
25°C-45°C; and
ii) adding a predetermined amount of the essential oil to the heated alcohol ethoxylate.
[0033] The preferred method of solubilising essential oil provided by the present invention
is advantageous in that it results in an essential oil solution wherein the weight
to weight ratio of surfactant to tea tree oil is relatively low. Weight to weight
ratios of less than 1 to 1 can be achieved by following the solubilisation method
of the present invention.
[0034] The low weight to weight surfactant to essential oil solutions are preferable for
the following reasons:
i) High weight to weight surfactant to essential oil mixtures often give rise to solutions
which are hazy, cloudy or opalescent. These cloudy or opalescent solutions are generally
not desirable for commercial reasons. The low weight to weight surfactant to essential
oil solutions can be diluted with water to produce bright clear solutions.
ii) A relatively high mass of surfactant can inhibit the broad spectrum germicidal
efficacy of an essential oil such as tea tree oil. The lower the weight surfactant
the higher the efficacy of natural oil as measured by standard Minimum Inhibitory
Concentration (MICS) analysis.
[0035] In a further preferred embodiment of the present invention, the solid composition
is in the shape of a disc.
[0036] In a further preferred embodiment the disc is a flat discus shape with a base surface
and a top surface and a side wall connecting the base surface to the top surface.
Preferably, the diameter of the top surface is less than the diameter of the base
surface.
[0037] In a preferred embodiment the ratio of the height of the side wall to the width (circumference)
of the top surface is between 1:10 and 1:11.5. For example, a preferred disc may have
a side wall height of 20 mm and a top surface width (circumference) of 230 mm. A disc
of the present invention may, for example, have the following dimensions:
Base surface: |
250 mm |
Top surface |
210 mm |
Height |
40 mm. |
[0038] In a further preferred embodiment the side wall is shaped in a camber. Preferably
the angle of connection between the base and top surfaces is equal to or less than
65 degrees and more preferably equal to or less than 62 degrees and 57 minutes.
[0039] In a further preferred embodiment the solid compositions of the present invention
have a total weight of between 0.5 and 5 kg. More preferably, the solid compositions
have a total weight of between 0.9 and 3 kg.
[0040] The preferred dimensions of a disc according to the present invention provide an
advantage in that a slow and even diffusion of natural oil from the disc occurs in
the presence of air flow.
[0041] In a third aspect the present invention provides a method of preparing a solid composition
which method includes
i) dissolving a gum material in an aqueous solution:
ii) heating the gum material solution to a temperature of between 60°C and 95°C:
iii) admixing the heated gum material solution with a tea tree oil/surfactant solution:
and
iv) placing the admixed solution from step iii) into a mould.
[0042] It will be appreciated that the present invention provides a simple and cost-effective
means for dispersing essential oils in a given environment. The solid compositions
of the present invention can be simply placed in air conditioning ducts by unskilled
labour so as to diffuse essential oils into the air stream.
[0043] Accordingly, in a fourth aspect the present invention provides a method of diffusing
tea tree oil into the atmosphere which method includes exposing a solid composition
including a gum material and the tea tree oil to an air flow such that the solid composition
releases vapour containing the tea tree oil.
[0044] In a preferred embodiment the solid composition is exposed to an air flow by placing
the solid composition in an air conditioning duct.
[0045] It will be appreciated that the preferred solid compositions of the present invention
also provide a simple and cost effective means of disinfecting air conditioning systems.
Unlike systems described in the prior art, the preferred compositions of the present
invention do not rely on solubilising the essential oil in alcohol or gaseous carbon
dioxide. The preferred non toxic water-based gum disc-shaped compositions allow germicidal
oil vapour to diffuse slowly and constantly in the presence of the air flow generated
in air conditioning ducting.
[0046] Accordingly, in a fourth aspect the present invention provides a method of disinfecting
an air conditioning system which method includes placing a solid composition in a
duct of the air conditioning system, the solid composition including a gum material
and tea tree oil, wherein the composition releases antimicrobial vapour containing
the tea tree oil when exposed to an effective flow of gas.
[0047] In a preferred embodiment, the essential oil is tea tree oil.
[0048] The term "air conditioning system" as used herein refers collectively to ducts, fans,
filters, humidifiers, coolers and other plant and equipment assembled for air conditioning
to parts of such systems.
Detailed description of the Invention
[0049] In order that the nature of the present invention may be more clearly understood
preferred forms thereof will now be described with reference to the following Examples.
Example 1
Tea Tree Oil Compositions
[0050] In a preferred embodiment of the invention the tea tree oil is manufactured in accordance
with the ISO 4730 standard. Preferably, the tea tree oil is a pharmaceutical grade
material. Table 1 describes the characteristics of an ISO 4730 standard tea tree oil.
In a most preferred embodiment the tea tree oil conforms with the ISO 4730 standard
prescribed in Table 1 but with component values in respect to 1,8 cineol less than
4% and preferably 2.2-3.0%; and terpinen-4-ol values greater than 37% and preferably
39-41%. Table 2 shows results of gas chromatic analysis for two batches of the preferred
TEETEEOH! brand pharmaceutical grade tea tree oil.
Table 1 The ISO Standard 4730 prescribes the following physical and component details for
Australian Single Distilled Tea Tree Oil - Oil of Melaleuca Alternifolia.
Physical |
Liquid |
State |
|
Colour |
Visually colourless to pale yellow |
Odour |
Typically Myristic |
Specific |
Method ISO 279 20 Degrees C/20 degrees C 0.885 - 0.906 |
Gravity |
|
Refractive |
Method ISO 280 |
Index |
1.475 to 1.482 |
Optical |
Method ISO 592 |
Rotation |
+ 5 degrees to + 15 degrees |
Solubility |
In 85% v/v Ethanol at 20 Degrees C the Miscibility should be such that one volume
of the oil shall require not more than two volumes of 85% ethanol to give a clear
solution |
This is tested in accordance with ISO Method 875 |
Flash Point |
Penskey Martens Closed Cup IP 34 |
In typical Range 57 degrees C to 60 Degrees C |
Fire Point |
Cleveland Open Cup IP 36-72 Degrees C. |
Component Range |
There are 15 components determined by gas chromatographic analysis in accordance with
method ISO 7609-1985 which are identified as being truly representative of genuine
oil of melaleuca alternifolia in the ISO 4730 standard. These are listed below. The
components described as Ledene (Viridiflorene), delta-Cadinene, Globulol and Viridiflorol
are each components found only in the prescribed rations in genuine oil of melaleuca
alternifolia and are said to be "genuine marker components for tea tree oil (oil of
melaleuca alternifolia)." |
|
|
Component |
ISO 4730 Range % |
alpha-Pinene |
1-6 |
Sabinene |
Trace - 3.5 |
alpha-Terpinene |
5-13 |
Limonene |
0.5-4 |
para-Cymene |
0.5-12 |
1,8 Cineole |
0-15 |
gamma-Terpinene |
10-28 |
Terpinolene |
1.5-5 |
Terpene-4-ol |
30 plus |
alpha-Terpineol |
1.5-8 |
Aromadendrene |
Trace-7 |
Ledene (Viridiflorene) |
0.5-6.5 |
delta-Cadinene |
Trace-8 |
Globulol |
Trace-3 |
Viridiflorol |
Trace-1.5 |
Table 2 Teeteeoh! Brand Pharmaceutical Single Distilled Australian Tea Tree Oil (Oil of Melaleuca
Alternifolia)
COMPONENT |
VALUE % |
ISO 4730 STANDARD % |
Batch Number 1029 |
alpha-Pinene |
2.7 |
1-6 |
Sabinene |
0.4 |
Trace-3.5 |
alpha-Terpinene |
9.7 |
5-13 |
Limonene |
1.0 |
0.5-4 |
para-Cymene |
2.7 |
0.5-12 |
1,8 Cineole |
2.8 |
0-15 |
gamma-Terpinene |
20.9 |
10-28 |
Terpinolene |
3.4 |
1.5-5 |
Terpinen-4-ol |
40.0 |
30 plus |
alpha-Terpineol |
2.5 |
1.5-8 |
Aromadenedrene |
1.3 |
Trace-7 |
Lendene (Viridiflorene) |
1.1 |
0.5-6.5 |
delta-cadinene |
1.1 |
Trace-8 |
Globulol |
0.4 |
Trace-3 |
Viridiflorol |
0.2 |
Trace-1.5 |
BATCH 1021 |
alpha-Pinene |
2.4 |
1-6 |
Sabinene |
0.6 |
Trace-3.5 |
alpha-Terpinene |
10.1 |
5-13 |
Limonene |
1.0 |
0.5-4 |
para-Cymene |
2.3 |
0.5-12 |
1,8 Cineole |
3.0 |
0-15 |
gamma-Terpinene |
20.8 |
10-28 |
Terpinolene |
3.4 |
1.5-5 |
Terpinen-4-ol |
41.4 |
30 plus |
alpha-Terpineol |
2.6 |
1.5-8 |
Aromadenedrene |
1.1 |
Trace-7 |
Lendene (Viridiflorene) |
0.9 |
0.5-6.5 |
delta-cadinene |
0.9 |
Trace-8 |
Globulol |
0.3 |
Trace-3 |
Viridiflorol |
0.2 |
Trace-1.5 |
Example 2
Tea tree oil solid composition
[0051] A carrageenan locust bean gum mixture is selected which has been standardised with
the addition of appropriate salts and polysaccharides so the mixture possesses the
following characteristics:
Viscosity: 400 to 600 centipoises measured as a 2.5% aqueous solution on a Brook field
RVT Viscometer, operating at 20 revolutions per minute and with solution heated to
70 degrees centigrade.
[0052] The pH of the Carrageenan, locust bean gum mixture is in the range 7-9% when a 1%
solution of the mixture is measured.
[0053] The particle size of the combined dried mixture is such that more than 98% is finer
than 250 microns. The total moisture content of the mixture is not greater than 14%.
The gel strength of the mixture is between 1800 and 2200 measured in a Kobe tester
a solution strength of 2.5%. The carrageenans are a mixture of kappa and iota component
containing types.
[0054] The water for first dispersing the carrageenan and locust bean gum mixture and then
heating to gelatinisation is de-ionised water.
[0055] The carrageenan locust bean gum mixture is first wetted to aid dispersion with ethanol.
A mixture of pure tea tree oil and surfactant is made. The tea tree oil is as described
above and conforms with ISO 4730. The actual tea tree oil used is TEETEEOH! Brand
Australian Single Distilled Pharmaceutical Grade with the following important component
values; the 1, 8 cineole is in the range 2.2-2.5% and the Terpinene-4-ol in the range
39-41%.
[0056] The surfactant used is polyoxyethylene (2) oleyl ether. The surfactant is measured
so that sufficient is available to solubilise the tea tree oil. The measured surfactant
is heated approximately 37 degree C. The carefully measured tea tree oil is poured
into the heated surfactant and stirred vigorously. The finished solution is bright
and clear. Sufficient de-ionised water is added to the surfactant-tea tree oil mixture
as is required. This bright clear mixture is set aside.
[0057] The wetted carrageenan-locust bean gum mixture described above is mixed with sufficient
cold water. The water temperature is no greater than 12 degrees C. The well dispersed
carrageenan-locust bean gum mixture is gradually heated with vigorous stirring to
90 degrees C. The mixture is held at 90 degrees C for several minutes. The mixture
is allowed to cool to 70 Degrees C. To the cooled carrageenan-locust bean gum mixture
is added the tea tree oil-surfactant solution. This has the immediate effect of rapidly
cooling the mixed solution further. The cool mixture is poured carefully into rubber
moulds. The moulds are formed so that the finished gel has a distinctive flat discus
shape as described previously. The surface area of the top of the discus shape is
preferably less than the surface area of the bottom of the discus shape. The ratio
of the height (side wall) of the discus to its surface is preferably of the order
of 1:10 or 1:11.5 but this ratio is not essential. The edge of the discus shape is
preferably carefully shaped so as to provide a gradual camber. This is preferable
so that even air diffusion takes place with the finished Tea Tree Gel Disc. The mixture
can be de-moulded with 30 minutes. The Tea Tree Gel-Discs so formed are allowed to
cool completely.
[0058] Upon complete cooling the discs may be packed in suitable plastic and further packed
in recyclable cardboard cartons. The plastic may be polyethylene-plastics does type
4, polypropylene-plastics code type 5, or preferably Fluorinated - High density Polyethylene-plastics
code type 2-modified. No colouring matter is used in the manufacture of any type of
Tea Tree Gel-Disc. The final Tea Tree Gel Disc in this example contains 10% tea tree
oil. The Tea Tree Gel Disc in this example has a shelf life of 12 months wrapped and
packaged. The tea Tree Gel Disc in this example has an unwrapped normal room air circulation
life of between 30 and 45 days.
[0059] When installed into an air conditioning ducting this Tea Tree Gel Disc may have a
life of between 7 and 10 days. The Gel Disc life in an air conditioning system is
dependent on the systems air flow and air temperature. The tea tree gel disc manufactured
in accordance with this method can be described as having low to very low syneresis.
Example 3
Tea tree oil solid composition
[0060] A carrageenan locust bean and xanthan gum mixture is selected which has been standardised
with the correct addition of salts and saccharides. The carrageenan has a viscosity
of 400 to 600 centipoises as measured in a 2.5% solution on a Brookfield RVT viscometer
at 20 revolutions per minute and solution heated to 70 degrees C. The pH of the carrageenan
in a 1% solution is between 7 and 9. The total moisture of the powder is 14%. The
carrageenan tests to a gel strength of 1800 to 2200 in a Kobe test measured at 2.5%
in de-ionised water. The carrageenan selected is a mixture of carrageenans containing
kappa and iota component carrageenans. This mixture is dry mixed with a selected xanthan
gum. The dry blended mixture is carefully weighed. To this weighed mixture is added
sufficient ethanol to aid dispersion in cold de-ionised water. The mixture is slowly
dispersed in di-ionised water with a commencement temperature of 12 degrees C. The
water is added so that the final gel mixture contains 3.8% selected hydrocolloids.
The mixture is gradually heated to 90 degrees C under constant stirring. The heated
mixture is held at 90 degrees C under constant stirring for several minutes. To this
mixture is added pre-prepared tea tree oil - surfactant solution of sufficient strength
so that the final gel-disc contains no less than 10% v/v tea tree oil. The Tea Tree
Oil in Pharmaceutical Standard Material conforming with ISO 4730.
[0061] The tea tree oil surfactant mixture is added to the hydrocolloid solution which has
been cooled to 70 degrees C. The mixture is carefully stirred and allowed to cool
further. It is then poured carefully into rubber moulds designed in accordance with
disc specifications previously described. The moulds are released within 30 minutes.
The gel discs are allowed to cool. Once cooled the Tea Tree Gel Discs may be packed
in suitable plastic film and packed in recyclable fibreboard.
[0062] The Tea Tree Gel Discs manufactured in accordance with the method may have an air
conditioning air diffusion life of between 7 and 10 days. The Gel Discs so produced
are bright, shiny and almost transparent. No colouring material is used. The tea tree
gel disc is manufactured in this manner can be described as having low syneresis.
Example 4
Tea tree oil solid composition
[0063] In this example only pure kappa component type carrageenan from the family Solieriaceae
species
Eucheuma cottonii is used. Further, the ethanol alcohol which is used to aid dispersion of the carrageenan
is also co-used to solubilise the pharmaceutical grade tea tree oil. No surfactants
are used in this example. To the carrageenan as selected is added dextrose monohydrate
and maltodexterin with a dextrose equivalent of between 17 and 21. The dry powder
is carefully wetted with a proportion of the ethanol and mixed. To this wetted mixture
is added cold water with a temperature of 12 degree C. The mixture is heated to 85
degrees C and held for exactly 2 minutes. This solution is cooled to 70 degrees C.
To the cooled mixture is added a pre mixed solution of ethanol and pharmaceutical
grade tea tree oil. The tea tree oil conforms with ISO 4730 standard. The mixture
is stirred vigorously. The rapidly cooling mixture is poured into suitable rubber
mould prepared in accordance with the disc specification described previously. Within
15 minutes the moulds are released and the Tea Tree Gel Discs removed. The Tea Tree
Gel Discs are allowed to cool completely. They may be packed in suitable plastic film
as described previously. The plastic wrapped tea tree gel discs may be packaged in
recyclable fibreboard boxes. The tea tree gel discs manufactured in this manner are
preferably bright and clear and have reasonably hard finished surface. The tea tree
gel disc made in the manner in this example have a tea tree oil content of 15%. The
solid hydrocolloid matter is 4.8% and the weight of the finished tea tree gel discs
is 900 grams. The air diffusion life in standard air conditioning ducting for this
example was between 7 and 10 days. These discs can be described as having low to very
low syneresis.
Example 5
Tea tree oil solid composition
[0064] Pure kappa component carrageenan derived from
Eucheuma cottonnii was used in this example. No additional salts or saccharides were used. The weighted
carrageenan was wetted only with commercial methylated spirits. The wetted kappa carrageenan
was thoroughly mixed and admixed with cold water at 20 degrees C. The mixture was
well dispersed. A pre-prepared mixture of pharmaceutical grade tea tree oil and ethanol
was then added to the cold kappa carrageenan mixture.. The proportion of ethanol to
tea tree oil in the pre-prepared mixture was approximately 2 parts ethanol to 1 part
tea tree oil. The complete mixture was stirred vigorously and heated slowly to 85
degrees C. The mixture was kept at 85 degrees C for approximatley 45 seconds. By way
of a jacketed mixer cold water with temperature of between 12 and 14 degrees C was
introduced into the jacket as a cooling medium. The mixture was rapidly cooled to
below 70 degrees C and poured directly into suitable moulds as previously described.
The moulds were released in 12 minutes. The tea tree gel discs allowed to cool. The
Tea Tree gel discs made in this manner contained 15% tea tree oil v/v and were carried
by a total dry hydrocolloid matter of 5%. The tea tree gel disc were packed as previously
described. These discs were found to have an air conditioning diffusion life of between
7 and 10 days. They can be described as low syneresis.
Example 6
Tea tree oil solid composition
[0065] A dry mixture of selected kappa and iota component carrageenans together with locust
bean gum, xanthan gum, dextrose monohydrate, 17 DE maltodextrin, and cations including
Sodium salts, Potassium salts and Calcium salts is carefully prepared. The weight
of this mixture is such that the weight of mixed hydrocolloid in the final preparation
is 3%. This mixture is wetted with ethanol. The mixture is carefully dispersed in
cold water of a temperature between 8 and 12 degrees C. The mixture is mixed in a
jacketed vessel with accurately controlled heating and cooling capabilities. The stirred
mixture is carefully heated to 86 degrees C and held at this temperature for 2 minutes.
To this mixture is added a surfactant solubilised pharmaceutical grade tea tree oil
mixture. The tea tree oil mixture is such that in the finished gel disc the tea tree
oil content will be 10% v/v. The tea tree oil surfactant mixture is added when the
hydrocolloid solution is at 65 degrees C. The total mixture is stirred carefully so
as to minimise formation of air bubbles. The cooling mixture is carefully poured into
the rubber moulds as previously described. Within 30 minutes the mould can be released.
The Tea Tree Gel Discs are left to cool for 24 hours prior to packing. The gel discs
made in this manner have very low syneresis. After 24 hours the tea tree gel discs
are packed in selected plastic film. The plastic film wrapped tea tree gel discs are
placed into recyclable fibreboard for storage and shipping. No colouring matter is
used and the tea tree gel discs have a pleasant opaque creamy to light brown colour.
The Tea Tree Gel Discs made in this way have very low syneresis. The rate of diffusion
in standard air conditioning systems may be 7 to 10 days depending on air flow and
temperature range. The net weight of tea tree gel disc made in this manner is 900
grams each. The total volume of tea tree oil dissipated in 168 hours is approximately
90 grams. In the first 24 hours 18 grams of tea tree oil is dissipated. This is an
approximate equivalent of 0.75 grams per hour in a typical air flow situation. This
is relatively low yet as per the experimental results described herein is highly effective
in the disinfecting of air conditioning ducting.
Example 7
Tea tree oil and lavender solid composition
[0066] A carrageenan locust bean gum mixture is selected which has been standardised with
the addition of appropriate salts and polysaccharides so the mixture possesses the
following characteristics:
[0067] Viscosity: 400 to 600 centipoises measured as a 2.5% aqueous solution on a Brookfield
RVT Viscometer, operating at 20 revolutions per minute and with solution heated to
70 degrees centigrade.
[0068] The pH of the Carrageenan locust bean gum mixture is in the range of 7-9 when a 1%
solution of the mixture is measured.
[0069] The particle size of the combined dried mixture is preferably such that more than
98% is finer than 250 microns, the total moisture content of the mixture is preferably
less than 14%. The gel strength of the mixture is between 1800 and 2200 measured in
a Kobe tester at solution strength of 2.5%. The carrageenans are a mixture of kappa
and iota component containing types.
[0070] The carrageenan locust bean gum mixture is first wetted to aid dispersion with ethanol.
A mixture of pure tea tree oil, oil of
Leptospermurn liversidgeii, oil of
Lavendula angustifolia (lavender) and surfactant is made. The tea tree oil is as already described and conforms
with ISO 4730. The additional oils are pure as defined by the Australian Standards.
[0071] The surfactant used is polyoxyethylene (20) oleyl ether. The surfactant is measured
so that sufficient is available to solubilise all the essential oils described.
[0072] The measured surfactant is heated to 37 degrees C. The measured essential oils are
poured into the heated surfactant and stirred vigorously. The finished solution is
preferably bright and clear. Sufficient water is added to the surfactant - essential
oil mixture as required. This bright highly fragrant mixture is set aside.
[0073] The wetted carrageenan - locust bean gum mixture described above is mixed with sufficient
cold water. The water temperature is no greater than 12 degrees C. The well dispersed
carrageenan-locust bean gum mixture is gradually heated with vigorous stirring to
90 degrees C and held at this temperature for several minutes. The mixture is allowed
to cool to 70 degrees C. To the cooled carrageenan-locust bean gum mixture is added
the essential oil - surfactant solution. This has the immediate effect of rapidly
cooling the mixed solution further.
[0074] The cooled mixture is poured into suitable moulds. The cooled discs are packed in
such a way as to have a shelf life of 12 months wrapped. Unwrapped discs have been
found to have an operational air conditioning ducting lift up to 30 days.
[0075] When installed into an air conditioning ducting the discs release a pleasant lavender
fragrance.
Example 8
Fragrant tea tree oil solid composition
[0076] In this example, custom made and chosen fragrant essential oil blends are selected,
so that when incorporated with polysaccharides as previously described, the fragrance
will diffuse into air conditioning ducting. Firstly, the fragrant essential oils are
selected and blended so that the chosen fragrance is the most powerful of all fragrances
present in the mixture. This blend of essential oils is then solubilised in a selected
volume of polyoxyethylene (20) oleyl ether. This mixture is then added to a pre-prepared
complex polysaccharide mixture which may comprise both kappa and iota type carrageenans
and locust bean gum and guar gum.
[0077] In this example the most dominant fragrance is that of German Camomile essential
oil derived from the species
Matricaria recutica.
[0078] The method of preparation is similar to other examples described herein.
Example 9
Tea tree oil and sandalwood solid composition
[0079] In this example and by way of demonstration that a single essential oil fragrant
note could be achieved, by combining only one other essential oil with the oil of
Melaleuca alternifolia (tea tree oil) as previously described. In this example only the oil of
Santalum album (sandalwood) was added to that of the tea tree oil.
[0080] Whilst maintaining the broad spectrum antimicrobial characteristics of tea tree oil
this example shows that the highly aromatic and myrsitic odour of tea tree oil can
be simply masked and overpowered by an essential oil such as sandalwood. This is surprising
given that sandalwood is described generally in essential oil and perfumery literature
as the base note essential oil having an evaporation rate of 100 according to the
index ascribed to Poucher. This index asserts that an oil with a maximum score of
100 has the slowest evaporation rate. By way of comparison, an oil such as lavender
which is given an index number of 4, is considered to be a top note essential oil.
[0081] The sandalwood tea tree oil mixture is combined with a sufficient amount of polyoxyethylene
(20) oleyl ether for solubilisation and the mixture added to a cooled mixture of complex
polysaccharides. The combined mix is then poured into a suitable mould to form a disc
shape as previously described.
[0082] The unwrapped discs so produced can deliver a pleasant fragrance when installed into
air conditioning ducting. In circumstances where the air conditioning fans are operating
(not necessarily the refrigeration) the sandalwood - tea tree oil solid composition
discs may last for up to 30 day.
Example 10
Summary of test results from trials conducted in air conditioning systems in a hospital
in New South Wales, Australia
[0083] The experimental parameters for establishing the broad spectrum germicidal efficacy
of the air diffused water gel tea tree oil solid compositions is described below:
[0084] An air conditioning ducting system was chosen in a major New South Wales Australia
Public Hospital.
[0085] This system operated on refrigerated air and the the refrigerant was of a non CFC
type. The air flow was variable to suit and was measured typically as cubic metres
per minute.
[0086] The temperature range of the air flow was measured and automatically controlled so
that at ducting inspection points the air temperature ranged between 11 degrees C
and 21 degrees C.
[0087] Specially adapted ease of access inspection ports were installed at the selected
air conditioning ducting.
[0088] Ducting with identical geometry was selected in two separate floors-nominated as
level 3 and level 4.
[0089] Only active air diffused water gel blocks containing water miscible tea tree oil
weer installed on level 3. On level 4 either no gel discs or only placebo gel discs
were installed for control purposes.
[0090] Installation was in the manner that two tea tree oil solid compositions were installed
within 600 mm either side of the inspection ducting, so that one solid composition
was up airstream and one down airstream from the inspection port.
[0091] The solid compositions were placed on the flat floor of each ducting either side
of the inspection port as described above.
[0092] The width of the ducting floor was at point 1 level 3 approx 600 mm. The width of
the ducting floor at point 2 level 3 was approximately 350 mm.
[0093] The ducting floor widths at identical inspection points on level 4 were approximately
the same as those on level 3.
[0094] The air flow into the ducting selected had an airstream which has been HEPA micro
filtered (High Efficiency Particulate Air Filtered).
[0095] The ducting systems on both level 3 and level 4 were carefully sampled for both air
and surface microbiological samples as per the accompanying table/s.
[0096] The sampling was carried out by independent Air Quality Surveyor using the most modern
air and surface sampling methods and equipment.
[0097] The sampling was further supervised by a qualified and practising microbiologist.
[0098] The solid compositions were produced by the method described in example 2 and were
installed on level 3 at 1 inspection point approximately 1 hour after this initial
sampling.
[0099] Further sampling was performed on the same active sites described as inspection points
1 and 2 on level 3 approximately 21 hours later.
[0100] Approximately 72 hours after the insertion of the first two solid compositions, which
were only installed at inspection point 1, an additional four solid compositions were
installed on level 3.
[0101] Two solid compositions were installed at inspection point 1 on either side of the
inspection port. Two solid compositions were installed at inspection point 2 level
3 on either side of the inspection port-in floor of the ducting.
[0102] The distance between inspection point 1 and 2 is approximately 20 metres.
[0103] First Microbiological samplings were taken prior to installation of the first two
solid compositions; further samplings were taken after the installation of the additional
four solid compositions; installed as two at each inspection point.
[0104] The results obtained from these samplings show clearly the microbiological efficacy
of the solid compositions.
[0105] The reduction in Fungal count within the first 21-24 hours was particularly significant
as fungal contamination of air conditioning ducting is of major concern to health
and sanitation authorities. The results show a greater than 100 fold reduction after
48 hours. In fact in the first 21 hour period the fungal reduction was greater than
800 fold being reduced from greater than 3200 colony forming units (CFU) to less than
4 CFU.
[0106] The rate of diffusion of the solid compositions was as predicted by small scale experimental
programmes and indicated as 20% within the first 24 hours, 20% in second 24 hours,
approximately 20% in the third 24 hour period. Thereafter the rate of diffusion was
at around 10% in each 24 hour period and reducing so that the total solid composition
had air diffused within the air conditioning ducting by the action of the air flow
existing within the system in a period of between 120-168 hours.
[0107] The results obtained from the trials above are further confirmation of the well published
efficacy data for tea tree oil which shows the Minimum Inhibitory Concentrations of
Australian Tea Tree oil for some organism as per the table below:
GRAM POSITIVE BACTERIA |
MIC% |
Bacillus cereus |
0.3 |
Bacillus subtilus |
0.3-0.4 |
Corynebacterium spp. |
0.2-0.3 |
Micrococcus luteus |
0.2-0.3 |
Propionibacterium acnes |
04-0.5 |
Methicillin resistant Staphylococcus aureus |
0.2-0.3 |
Staphylococcus epidermis |
0.5 |
Enterococcus faecalis |
0.5-0.75 |
GRAM NEGATIVE BACTERIA |
MIC% |
Enterobacter aerogenes |
0.3 |
Eschericia coli |
0.2 |
Klebsiella pneumonia |
0.3 |
Proteus vulgaris |
0.2-0.3 |
Pseudomonas putida |
0.5 |
Serratia marcescens |
0.2-0.3 |
FUNGI AND YEASTS |
MIC% |
Aspergillus niger |
0.3-0.4 |
Aspergillus flavus |
0.4-0.5 |
Candida albicans |
0.2 |
Piryrosporum ovales |
0.2 |
Trychophyton mentagrophytes |
0.3-0.4 |
Trychophyton rubrum |
1.0 |
Example 11
Summary of test results from trials conducted in air conditioning system in a public
hospital in New South Wales, Australia
[0108] Sampling performed by Air Quality Services Pty Ltd and Microbiological examination
of the samples performed by Biotech Laboratories Pty Ltd Queensland.
Test Area
[0109] Air conditioning air ducting system. The system comprises straight ducting with two
in - place inspection points at approximately 25 metres apart.
Air Supply
[0110] The system is refrigerated and works on constant supply 24 hours 7 days per week.
The air is HEPA filtered.
Microbiological Sampling
[0111] Sampling for airborne bacteria, airborne fungi and mould, surface bacteria and surface
yeast and mould was performed by sterile swab and automatic air sampling apparatus.
Solid Composition Tea Tree Oil Gel Discs
[0112] Solid compositions for this test were produced according to the method described
in Example 2. Two each with a total mass of 2.2 kilograms were placed at each inspection
point. The water solubilised tea tree oil content in each gel disc was 22%v/v.
Sampling Procedure
[0113] Samples were taken prior to installing the gel discs. The gel discs were installed
either side of the inspection hatch and placed directly on the floor of the air conditioning
ducting.
Bacteria
[0114] Both surface and airborne bacteria levels tested were shown to be so insignificant
as unnecessary to be reported in these results.
Surface Yeast and Mould and Airborne Fungi and Mould
[0115] These tests indicated very high microbiological contamination.
RESULTS
[0116]
Date |
05/11/96 |
06/11/96 |
13/11/96 |
19/11/96 |
SURFACE YEAST AND MOULD CFU/cm |
LEVEL 3 |
24 Hour Result |
Final Result |
ACCESS POINT 1 |
Temp/C 12 |
Temp/C 20 |
Temp/C 15 |
Temp/C 13 |
Against Flow |
44 |
36 |
160 |
20 |
With Flow |
8 |
120 |
100 |
8 |
Hatch |
> 1200 |
4 |
< 4 |
< 4 |
Hatch |
8 |
< 4 |
< 4 |
< 4 |
ACCESS POINT 2 |
Against Flow |
> 1200 |
< 4 |
12 |
8 |
With Flow |
16 |
8 |
8 |
4 |
Hatch |
<4 |
<4 |
<4 |
<4 |
Hatch |
<4 |
16 |
<4 |
<4 |
AIRBORNE FUNGI AND MOULD CFU/cm |
ACCESS POINT 1 |
Against Flow |
150 |
50 |
<50 |
<50 |
With Flow |
100 |
150 |
<50 |
100 |
ACCESS POINT 2 |
Against Flow |
150 |
50 |
<50 |
<50 |
With Flow |
<50 |
200 |
50 |
>50 |
[0117] The tea tree oil solid compositions were installed on 5/11/96 (after initial samples
taken). These results show significant surface yeast and mould at the start of the
trial. The 24 hour reduction (as measured on 6/11/96) of the greater than 1200 CFU
values indicate the efficacy of the solid tea tree oil gel discs. The final 14 day
results further indicate this efficacy.
[0118] Airborne Fungi and Mould can be described as insignificant levels. A statistical
reduction is observed.
Example 12
Test conditions and results obtained from trials conducted in a major public Bowling
Club in Northern New South Wales - Australia.
[0119] Sampling performed by Air Quality Services Pty Ltd and Microbiological examination
of the samples performed by Biotech Laboratories Pty Ltd Queensland.
Test Area
[0120] Air conditioning air ducting system/s. The system is a mixed one. One air handler
supplying quite direct air flow to destination terminals. Another had a split air
flow system and ducting constructed with large curvature in many places.
[0121] Sampling was also performed in a public area access site at the point furthest from
the air handler. This site was at a point in a bistro area - in the ceiling close
to a window. Sampling was also performed at a public point described as cashier.
Air Supply
[0122] The system is refrigerated. The system is idyll for up to 11 hours daily. For part
of these trials one air handler was re-set so that the fans worked continuously for
24 hours each day for 7 days. The refrigeration unit was maintained as operational
for between 9 and 11 hours. The air is filtered prior to entry into the ducting.
Microbiological Sampling
[0123] Sampling for airborne bacterium, airborne fungi and mould, surface bacteria and surface
yeast and mould was performed by sterile swab and automatic air sampling apparatus.
Solid Tea Tree Oil Compositions
[0124] In order to fully test the efficacy of the solid composition a number of compositions
made according to Example 2 were employed.
Sampling Procedure
[0125] Samples were taken prior to installing the gel discs. The gel discs were installed
either side of the inspection hatch and placed directly on the floor of the air conditioning
ducting.
Bacteria
[0126] Surface bacteria valued found are insignificant. Airborne values are higher - but
may be considered also to be unimportant so far as building health is concerned.
Surface Yeast and Mould and Airborne Fungi and Mould
[0127] These are considered high. Species are identified but not described in detail.
Airborne Fungi and Mould
[0128] Generally not considered excessive. Results for the public area are indicated for
interest.
Temperature and Relative Humidity
[0129] Temperatures fluctuated considerably. The relative humidity was high but in line
with local atmospheric conditions for the summer period in northern New South Wales.
RESULTS
TEST SITE A - UPPER CASINO
[0130]
YEAST AND MOULD CFU/cm2
ACCESS POINT 1 |
04/02/97 |
11/02/97 |
18/02/97 |
Hatch Door |
20 |
< 4 |
4 |
Hatch Door |
<4 |
<4 |
<4 |
Ducting Floor |
640 |
320 |
160 |
Ducting Floor |
960 |
640 |
440 |
ACCESS POINT 2 |
CASHIER-PUBLIC PLACE |
Duct wall - side |
510 |
240 |
330 |
Duct wall - rear |
180 |
200 |
92 |
[0131] On the start date, 04/02/97, one composition (10%v/v tea tree oil) was installed
after sampling. At the test time 11/02/97 there were only a few grams of the single
10% tea tree oil discs remaining in the ducting.
[0132] On the 18/02/97, two further 10 %v/v tea tree oil compositions were installed. These
discs were designed to have slow diffusion rates.
ACCESS POINT 1 |
25/02/97 |
04/03/97 |
Hatch Door |
4 |
8 |
Hatch Door |
< 4 |
< 4 |
Ducting Floor |
< 1200 |
140 |
Ducting Floor |
< 1200 |
220 |
[0133] At test 25/02/97 it was found that the solid compositions had diffused slowly and
were greater than 80% intact. Following sampling, two further 15% v/v tea tree oil
solid compositions were installed. These compositions had a gel type as described
in Example 2 and allowed for greater diffusion rate to compensate for the limited
air flow in the system.
[0134] The results on 04/03/97 confirm positively this course of action with a reduction
in CFUs from < 1200 to 140 and 220
[0135] The trials generally indicated a highly contaminated ducting environment and continued
as follows.
ACCESS POINT 1 |
11/03/97 |
18/03/97 |
25/03/97 |
Hatch Door |
<4 |
4 |
<4 |
Hatch Door |
<4 |
<4 |
<4 |
Ducting Floor |
380 |
120 |
220 |
Ducting Floor |
570 |
1200 |
84 |
[0136] After 11/03/97 no further solid compositions were installed. The air flow was very
poor during week of 18/03/97. At 25/03/97 the compositions had diffused by about 95%.
[0137] These tests confirm that the air conditioning fan system is preferably running fully
for each 24 hour period to fully maximise the solid composition potential. The refrigeration
may be employed only for the commercial times required by the operator - in this instance
9-13 hours daily. Running the fans is a low energy cost. The general benefits of moving
large air mass around public facilities irrespective of tea tree oil gel solid composition
disinfection are considerable.
[0138] Species of micro-organisms were identified during these trials. No conclusive evidence
was obtained to indicate the tea tree oil disinfection process is more specific for
the elimination of any particular type.
[0139] The most dominant species present was
Cladosporium herbarium, with
Penicillium species the next most dominant.
Aspergillus and
Candida were also observed. It was noted that the
Aspergillus only appeared after human intervention with the installation of a new inspection
hatch at one ducting site.
TEST SITE B - TERRACE BISTRO
ACCESS POINT 4
[0140] Adjacent to a Window in the public bistro area. This area is some 70 metres from
the insertion point of the Tea Tree Oil Solid Compositions in the ducting. For four
weeks in the trial sampling was conducted as shown below:
|
|
CFU/cm |
|
|
|
04/02/97 |
11/02/97 |
18/02/97 |
25/02/97 |
Duct Wall-Side |
> 1200 |
> 1200 |
> 1200 |
> 1200 |
Duct Wall-Rear |
> 1200 |
> 1200 |
> 1200 |
> 1200 |
[0141] On the 04/03/97, one solid composition of the present invention was installed. The
count was more fully enumerated following this installation.
|
04/03/97 |
11/03/97 |
18/03/97 |
25/03/97 |
Duct Wall-Side |
12000 |
2700 |
18400** |
2600 |
Duct Wall-Rear |
6800 |
2100 |
1900 |
1400 |
** This anomalous result may be due in part to the reduction in air flow that week.
No further compositions were placed in this area after 04/03/97. It is noted that
the extremely high counts at this point were effectively reduced over 4 weeks by the
insertion only of one 2.2 kilogram tea tree oil solid compostion. The significant
reduction within one week of these trials - between the 04/03/97 to 11/03/97 indicate
that in an area of high infection such as this, solid compostions can be applied at
more regular intervals, or in greater mass per composition. |
Test Conclusions
[0142] Air flow is preferably continuous. Fans can be left running at low cost. Refrigeration
can be employed as required. High relative humidity values are conducive to formation
of surface yeast and moulds constant air flow reduces this risk. Tea tree gel discs
are preferably moderate release type. Optimum tea tree level found to be 15% v/v.
Split air flow ducting - generally considered outdated - must be clearly identified
and cycles shown so that tea tree oil disc insertion points can be clearly determined.
Tea tree oil gel disc are clearly effective in the elimination of fungus, moulds and
yeasts and the maintenance of low bacteria counts in commercial air conditioning ducting.
[0143] These examples demonstrate that the Tea Tree Oil Solid Composition of the present
invention is highly effective and safe air conditioning ducting system sanitiser.
The composition is particularly effective against high mould, fungus and yeast micro-organism
numbers. The presence of such high levels of micro-organisms is now recognised as
posing a serious health risk to the buildings occupants.
[0144] The composition is particularly effective in well controlled refrigerated air conditioning
systems which run continuously. The constant air flow in such systems allows for even
diffusion rates of the solid composition tea tree oil gel discs.
[0145] The composition was found to be effective in commercial systems which operated fully
for only limited times during any 24 hour period. The trials demonstrated a low cost
way for such facilities to further improve the general air quality of their systems.
By limiting the generation of refrigerated air to the times selected and at other
times running the fans only, the solid composition worked more effectively and the
overall air quality improved.
[0146] In badly infected systems, the solid composition can return the system to normal
and accepted base line values for resident fungal micro-organisms. By thereafter employing
regular placement of the solid composition in air conditioning facilities these levels
are economically and efficiently maintained.
[0147] It will be appreciated by persons skilled in the art that numerous variations and/or
modifications may be made to the invention as shown in the specific embodiments without
departing from the spirit or scope of the invention as broadly described. The present
embodiments are, therefore, to be considered in all respects as illustrative and not
restrictive.
1. A solid composition including tea tree oil and from 2 to 10 wt% of a gum material
wherein the solid composition releases vapour containing, the tea tree oil when exposed
to an effective flow of gas.
2. A solid composition according to claim 1 wherein the gum material is a carrageenan
which preferably includes kappa, iota lambda fraction of a mixture of one or more
of the fractions.
3. A solid composition according to claim 1 or claim 2 wherein the gum material includes
a galactomannan which preferably has a molecular weight of approximately 300,000.
4. A solid composition according to claim 3 wherein the galactomannan is derived from
the legume Ceratonia siliqua and is preferably locust bean gum.
5. A solid composition according to any preceding claim wherein the gum material includes
a microbial exudate, preferably Xanthan gum.
6. A solid composition according to claim 1 wherein the gum material includes a mixture
of two or more components selected from the group consisting of a carageenan, locust
bean gum and Xanthan gum.
7. A solid composition according to any preceding claim wherein the gum material is present
in the solid composition at a concentration of from 3 to 6 wt%.
8. A solid composition according to any preceding claim which further includes an aromatic
oil which is preferably selected from at least one of the group consisting of heliotropin,
lavender, camomile, a lemon scented oil, the oil of Leptospermum liversidgeii, sandalwood and jasmine.
9. A solid composition according to claim 8 wherein the aromatic oil is sandalwood.
10. A solid composition according to claim 8 or claim 9 which further includes a fixative
which is preferably selected from the group consisting of musk ketone, coumarin, eugenol
and vanillin.
11. A solid composition according to claim 10 wherein the fixative is eugenol.
12. A solid composition according to any preceding claim wherein the natural oil is solubilised
by admixture with a non-ionic surfactant which is preferably an alcohol ethoxylate.
13. A solid composition according to claim 12 wherein the alcohol ethoxylate is polyoxyethylene(2)oleyl
ether.
14. A solid composition according to any preceding claim wherein the solid composition
is in the shape of a flat discus with a base surface and a top surface and a side
wall connecting the base surface to the top surface.
15. A solid composition according to claim 14 wherein the diameter of the top surface
is less than the diameter of the base surface.
16. A solid composition according to claim 14 or claim 15 wherein the ratio of the height
of the side wall to the width of the top surface is from 1:10 to 1:11.5.
17. A solid composition according to any one of claims 14 to 16 wherein the side wall
is shaped in a camber.
18. A solid composition according to any one of claims 14 to 17 wherein the angle of connection
between the base and top surfaces is equal to or less than 65 degrees.
19. A solid composition according to any preceding claim wherein the solid composition
has a total weight of from 0.5 to 5 kg, preferably from 0.9 to 3 kg.
20. Use of a solid composition for disinfecting an air conditioning system, the composition
including a gum material and a tea tree oil, wherein the solid composition releases
vapour containing the tea tree oil when exposed to an effective flow of gas.
21. Use of a solid composition according to claim 20, wherein the solid composition is
as described in any one of claims 1 to 19.
22. A method of preparing a solid composition according to claim 1 which method includes
i) dissolving a gum material in an aqueous solution;
ii) heating the gum material solution to a temperature of from 60°C to 95°C;
iii) admixing the heated gum material solution with tea tree oil solution; and
iv) placing the admixed solution from step iii) into a mould.
23. A method according to claim 22 wherein the tea tree oil solution is in admixture with
a non-ionic surfactant whichis preferably an alcohol ethoxylate.
24. A method according to claim 23 wherein the alcohol ethoxylate is polyoxyethylene (2)
oleyl ether.
25. A method of diffusing tea tree oil into the atmosphere which method includes exposing
a solid composition including a gum material and tea tree oil to an air flow such
that the solid composition releases vapour containing the tea tree oil.
26. A method according to claim 25 wherein the solid composition further includes an aromatic
oil.
27. A method according to claim 25 or claim 26 wherein the solid composition is exposed
to an air flow by placing the solid composition in an air conditioning duct.
28. A method of disinfecting an air conditioning system which method includes placing
a solid composition in a duct of the air conditioning system, the solid composition
including a gum material and tea tree oil, wherein the composition releases antimicrobial
vapour containing the tea tree oil when exposed to an effective flow of gas.
29. A method according to claim 28 wherein the solid composition further includes an aromatic
oil.
1. Feste Zusammensetzung, umfassend Teebaumöl und von 2 bis 10 Gew.-% eines Gummimaterials,
worin die feste Zusammensetzung Dampf freisetzt, der das Teebaumöl enthält, wenn es
einem wirkungsvollen Gasstrom ausgesetzt wird.
2. Feste Zusammensetzung nach Anspruch 1, worin das Gummimaterial ein Carrageenan ist,
das vorzugsweise die kappa-, iota- oder lambda-Fraktion eines Gemisches aus einer
oder mehreren der Fraktionen umfasst.
3. Feste Zusammensetzung nach Anspruch 1 oder Anspruch 2, worin das Gummimaterial ein
Galactomannan umfasst, das vorzugsweise ein Molekulargewicht von ungefähr 300000 aufweist.
4. Feste Zusammensetzung nach Anspruch 3, worin das Galactomannan von der Hülsenfrucht
Ceratonia siliqua stammt und vorzugsweise Johannisbrotgummi ist.
5. Feste Zusammensetzung nach einem der vorhergehenden Ansprüche, worin das Gummimaterial
ein mikrobielles Exsudat, vorzugsweise Xanthangummi, umfasst.
6. Feste Zusammensetzung nach Anspruch 1, worin das Gummimaterial ein Gemisch aus zwei
oder mehreren Komponenten, ausgewählt aus der Gruppe, bestehend aus einem Carrageenan,
Johannisbrotgummi und Xanthangummi, umfasst.
7. Feste Zusammensetzung nach einem der vorhergehenden Ansprüche, worin das Gummimaterial
in der festen Zusammensetzung in einer Konzentration von 3 bis 6 Gew.-% vorliegt.
8. Feste Zusammensetzung nach einem der vorhergehenden Ansprüche, weiterhin umfassend
ein aromatisches Öl, das vorzugsweise ausgewählt ist aus mindestens einem aus der
Gruppe, bestehend aus Heliotropin, Lavendel, Kamille, einem Zitronen-Duftöl, dem Öl
von Leptosperum liversidgeii, Sandelholz und Jasmin.
9. Feste Zusammensetzung nach Anspruch 8, worin das aromatische Öl Sandelholz ist.
10. Feste Zusammensetzung nach Anspruch 8 oder 9, weiterhin umfassend ein Fixierungsmittel,
das vorzugsweise ausgewählt ist aus der Gruppe, bestehend aus Moschusketon, Cumarin,
Eugenol und Vanillin.
11. Feste Zusammensetzung nach Anspruch 10, worin das Fixierungsmittel Eugenol ist.
12. Feste Zusammensetzung nach einem der vorhergehenden Ansprüche, worin das natürliche
Öl solubilisiert ist durch Mischen mit einem nichtionischen oberflächenaktiven Mittel,
das vorzugsweise ein Alkoholethoxylat ist.
13. Feste Zusammensetzung nach Anspruch 12, worin das Alkoholethoxylat Polyoxyethylen(2)oleylether
ist.
14. Feste Zusammensetzung nach einem der vorhergehenden Ansprüche, worin die feste Zusammensetzung
in der Form einer flachen Scheibe mit einer unteren Fläche und einer oberen Fläche
und einer Seitenwand, die die untere Fläche mit der oberen Fläche verbindet, ist.
15. Feste Zusammensetzung nach Anspruch 14, worin der Durchmesser der oberen Fläche kleiner
als der Durchmesser der unteren Fläche ist.
16. Feste Zusammensetzung nach Anspruch 14 oder 15, worin das Verhältnis der Höhe der
Seitenwand zur Breite der oberen Fläche von 1:10 bis 1:11,5 ist.
17. Feste Zusammensetzung nach einem der Ansprüche 14 bis 16, worin die Seitenwand als
eine Kammer geformt ist.
18. Feste Zusammensetzung nach einem der Ansprüche 14 bis 17, worin der Verbindungswinkel
zwischen den unteren und oberen Flächen gleich oder kleiner 65 Grad ist.
19. Feste Zusammensetzung nach einem der vorhergehenden Ansprüche, worin die feste Zusammensetzung
ein Gesamtgewicht von 0,5 bis 5 kg, vorzugsweise von 0,9 bis 3 kg, aufweist.
20. Verwendung einer festen Zusammensetzung zum Desinfizieren eines Klimaanlagesystems,
wobei die Zusammensetzung ein Gummimaterial und ein Teebaumöl umfasst, worin die feste
Zusammensetzung Dampf freisetzt, der das Teebaumöl enthält wenn es einem wirkungsvollen
Gasstrom ausgesetzt wird.
21. Verwendung einer festen Zusammensetzung nach Anspruch 20, worin die feste Zusammensetzung
so ist wie in einem der Ansprüche 1 bis 19 beschrieben.
22. Verfahren zum Herstellen einer festen Zusammensetzung nach Anspruch 1, wobei das Verfahren
i) Lösen eines Gummimaterials in einer wässrigen Lösung;
ii) Erhitzen der Gummimateriallösung auf eine Temperatur von 60 °C bis 95 °C;
iii) Mischen der erhitzen Gummimateriallösung mit einer Teebaumöllösung; und
iv) Anordnen der Gemischlösung aus Schritt iii) in einer Form umfasst.
23. Verfahren nach Anspruch 22, worin die Teebaumöllösung im Gemisch mit einem nichtionischen
oberflächenaktiven Mittel ist, das vorzugsweise ein Alkoholethoxylat ist.
24. Verfahren nach Anspruch 23, worin das Alkoholethoxylat Polyethylen(2)oleylether ist.
25. Verfahren zum Einbringen von Teebaumöl in die Atmosphäre, wobei das Verfahren das
Aussetzen einer festen Zusammensetzung, die ein Gummimaterial und Teebaumöl enthält,
einem Luftstrom umfasst, sodass die feste Zusammensetzung Dampf freisetzt, der das
Teebaumöl enthält.
26. Verfahren nach Anspruch 25, worin die feste Zusammensetzung weiterhin ein aromatisches
Öl umfasst.
27. Verfahren nach Anspruch 25 oder Anspruch 26, worin die feste Zusammensetzung einem
Luftstrom ausgesetzt wird durch Anordnen der festen Zusammensetzung in einer Klimaanlagenleitung.
28. Verfahren zum Desinfizieren eines Klimaanlagensystems, worin das Verfahren das Anordnen
einer festen Zusammensetzung in einer Leitung des Klimaanlagesystems umfasst, wobei
die feste Zusammensetzung ein Gummimaterial und Teebaumöl umfasst, worin die Zusammensetzung
antimikrobiellen Dampf, der das Teebaumöl enthält, freisetzt wenn sie einem wirkungsvollen
Gasfluss ausgesetzt wird.
29. Verfahren nach Anspruch 28, worin die feste Zusammensetzung weiterhin ein aromatisches
Öl umfasst.
1. Composition solide comprenant de l'huile d'arbre à thé et de 2 à 10 % en poids d'un
matériau de gomme, dans laquelle la composition solide libère de la vapeur contenant
l'huile d'arbre à thé lorsqu'elle est exposée à un écoulement effectif de gaz.
2. Composition solide selon la revendication 1, dans laquelle le matériau de gomme est
un carrageenan qui comprend de préférence une fraction kappa, iota ou lambda ou un
mélange d'une ou plusieurs des fractions.
3. Composition solide selon la revendication 1 ou la revendication 2, dans laquelle le
matériau de gomme comprend un galactomannane qui présente de préférence un poids moléculaire
d'approximativement 300 000.
4. Composition solide selon la revendication 3, dans laquelle le galactomannane est dérivé
du légume Ceratonia siliqua et est de préférence de la gomme de caroube.
5. Composition solide selon l'une quelconque des revendications précédentes, dans laquelle
le matériau de gomme comprend un exsudat microbien, de préférence de la gomme xanthane.
6. Composition solide selon la revendication 1, dans laquelle le matériau de gomme comprend
un mélange de deux ou plusieurs constituants choisis parmi un carrageenan, de la gomme
de caroube et de la gomme xanthane.
7. Composition solide selon l'une quelconque des revendications précédentes, dans laquelle
le matériau de gomme est présent dans la composition solide à une concentration de
3 à 6 % en poids.
8. Composition solide selon l'une quelconque des revendications précédentes qui comprend
en outre une huile aromatique qui est de préférence choisie parmi l'héliotropine,
la lavande, la camomille, une huile parfumée au citron, l'huile de Leptospermum liversidgeii, le bois de santal et le jasmin.
9. Composition solide selon la revendication 8, dans laquelle l'huile aromatique est
le bois de santal.
10. Composition solide selon la revendication 8 ou la revendication 9 qui comprend en
outre un fixatif qui est de préférence choisi parmi une cétone de musc, la coumarine,
l'eugénol et la vanilline.
11. Composition solide selon la revendication 10, dans laquelle le fixatif est l'eugénol.
12. Composition solide selon l'une quelconque des revendications précédentes, dans laquelle
l'huile naturelle est solubilisée par mélange avec un tensioactif non ionique qui
est de préférence un éthoxylate d'alcool.
13. Composition solide selon la revendication 12, dans laquelle l'éthoxylate d'alcool
est un polyoxyéthylène(2)oléyléther.
14. Composition solide selon l'une quelconque des revendications précédentes, dans laquelle
la composition solide est dans la forme d'un disque plat avec une surface de base
et une surface de haut et une paroi latérale connectant la surface de base à la surface
de haut.
15. Composition solide selon la revendication 14, dans laquelle le diamètre de la surface
de haut est inférieur au diamètre de la surface de base.
16. Composition solide selon la revendication 14 ou la revendication 15, dans laquelle
le rapport de la hauteur de la paroi latérale à la largeur de la surface de haut est
compris entre 1:10 et 1:11,5.
17. Composition solide selon l'une quelconque des revendications 14 à 16, dans laquelle
la paroi latérale est façonnée dans une courbure sphérique.
18. Composition solide selon l'une quelconque des revendications 14 à 17, dans laquelle
l'angle de connexion entre les surfaces de base et de haut est égal ou inférieur à
65 degrés.
19. Composition solide selon l'une quelconque des revendications précédentes, dans laquelle
la composition solide présente un poids total de 0,5 à 5 kg, de préférence de 0,9
à 3 kg.
20. Utilisation d'une composition solide pour désinfecter un système de climatisation
d'air, la composition comprenant un matériau de gomme et une huile d'arbre à thé,
dans laquelle la composition solide libère de la vapeur contenant l'huile d'arbre
à thé lorsqu'elle est exposée à un écoulement effectif de gaz.
21. Utilisation d'une composition solide selon la revendication 20, dans laquelle la composition
solide est comme décrit dans l'une quelconque des revendications 1 à 19.
22. Procédé de préparation d'une composition solide selon la revendication 1, lequel procédé
comprend :
i) la dissolution d'un matériau de gomme dans une solution aqueuse ;
ii) le chauffage de la solution de matériau de gomme à une température de 60°C à 95°C
;
iii) le mélange de la solution de matériau de gomme chauffée avec une solution d'huile
d'arbre à thé ; et
iv) la disposition de la solution mélangée de l'étape iii) dans un moule.
23. Procédé selon la revendication 22, dans lequel la solution d'huile d'arbre à thé est
mélangée avec un tensioactif non ionique qui est de préférence un éthoxylate d'alcool.
24. Procédé selon la revendication 23, dans lequel l'éthoxylate d'alcool est un polyoxyéthylène(2)oléyléther.
25. Procédé de diffusion d'huile d'arbre à thé dans l'atmosphère, lequel procédé comprend
l'exposition d'une composition solide comprenant un matériau de gomme et de l'huile
d'arbre à thé à un écoulement d'air de telle sorte que la composition solide libère
de la vapeur contenant l'huile d'arbre à thé.
26. Procédé selon la revendication 25, dans lequel la composition solide comprend en outre
une huile aromatique.
27. Procédé selon la revendication 25 ou la revendication 26, dans lequel la composition
solide est exposée à un écoulement d'air en plaçant la composition solide dans une
canalisation de climatisation d'air.
28. Procédé de désinfection d'un système de climatisation d'air, lequel procédé comprend
la disposition d'une composition solide dans une canalisation du système de climatisation
d'air, la composition solide comprenant un matériau de gomme et de l'huile d'arbre
à thé, dans lequel la composition libère des vapeurs antimicrobiennes contenant l'huile
d'arbre à thé lorsqu'elle est exposée à un écoulement effectif de gaz.
29. Procédé selon la revendication 28, dans lequel la composition solide comprend en outre
une huile aromatique.